The present invention relates to an apparatus for cutting grass and the like, which can be hitched in front of a motor unit.
In the technical sector relating to the cutting of grass, cutting devices with helical blades are known, said devices being substantially in the form of carriages formed by a plurality of helically twisted blades which are arranged around a rotating shaft mounted on wheels and which rotate integrally therewith as a result of driving of the carriage produced by the operator either manually or by means of special motor units to which the carriages are attached in the manner of a trailer.
It is also known that the cutting of grass with trailer devices gives rise to problems in that the motor unit, passing before the blades, crushes the grass and makes cutting more difficult; in addition, it is more difficult to perform visual control of the cutting direction and operation of the blades which require long stretches of ground in order to be able to straighten up after a bend, thereby complicating the manoeuvres and basically preventing the use of the devices in small plots such as gardens and the like.
It has therefore been attempted arranging the helical-blade carriages in position in front of the motor unit, but, since it is not possible to take advantage of the towing effect, it has been necessary to provide the said carriages with auxiliary motor means, separate from the motor unit, for operation of the blades, with a consequent increase in the technical design difficulties, the installation and management costs and maintenance requirements.
The technical problem which is posed, therefore, is that of providing an apparatus for cutting grass, with helical-blade devices, which can be hitched in front of special motor units without the need for auxiliary motors for operating the blades.
Within the scope of this problem a further requirement is that the apparatus should have small dimensions, allow easy operation and preferably be provided with means for rapid return of the blades into a position of alignment with the longitudinal axis of the motor unit after cutting along a section which is not straight.
These technical problems are solved according to the present invention by an apparatus for cutting grass which can be hitched to a motor unit and comprises a carriage with a shaft carrying associated wheels and helical blades rotating about said shaft, which apparatus comprises at least one support frame to which a rotational pin substantially perpendicular to the ground to be cut is attached, said vertical pin having, connected to it, a first end of an arm which is substantially parallel to the ground, the other end thereof being pivotably mounted on the carriage so that the end of the arm connected to the frame is in a position in front of the shaft of the carriage in the direction of forward movement of the apparatus.
Further details may be obtained from the following description of a non-limiting example of embodiment provided with reference to accompanying drawings, in which: